PSA: if you scorched Icarus with Modred's outrage ability, she will behave as if she scorched herself (i.e. not AoE outside of OD.) However, that isn't necessarily a good thing 'cos Mordred's scorch does like 5k dmg while Icarus is 275k (my 45k power all SR Mordred run failed because of this, will try again tomorrow.)

I have also heard reports of Mordred's scorch overwriting Icarus'. I haven't been able to verify it myself, but if your plan relies on Icarus scorching herself to death, it may be best to avoid casting outrage on Icarus (which makes Mordred even more useless; Sieg might actually be easier if you managed to make it to Icarus without using up all your potions.)